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Introduction: Neuroectodermal tumors in general demonstrate high and dense expression of the somatostatin receptor subtype 2 (sst). It controls proliferation of both normal and neoplastic cells. sst has thus been suggested as a therapeutic target and prognostic marker for certain malignancies. Methods: To assess global expression patterns of sst mRNA, we evaluated normal ( n = 353) and tumor tissues ( n = 340) derived from previously published gene expression profiling studies. These analyses demonstrated specific upregulation of sst mRNA in medulloblastoma ( p < 0.001). sst protein was investigated by immunohistochemistry in two independent cohorts. Results: Correlation of sst protein expression with clinicopathological variables revealed significantly higher levels in medulloblastoma ( p < 0.05) compared with CNS-PNET, ependymoma, or pilocytic astrocytoma. The non-SHH medulloblastoma subgroup tumors showed particularly high expression of sst, when compared to other tumors and normal tissues. Furthermore, we detected a significant survival benefit in children with tumors exhibiting high sst expression ( p = 0.02) in this screening set. A similar trend was observed in a validation cohort including 240 independent medulloblastoma samples. Conclusion: sst is highly expressed in medulloblastoma and deserves further evaluation in the setting of prospective trials, given its potential utility as a prognostic marker and a therapeutic target. [ABSTRACT FROM AUTHOR]